#include<bits/stdc++.h>

using namespace std;

int main() {

    char c = '0';//(const char*) cstring

    //cout<<(int)c;
    cout << "digit:";
    for (int i = 0; i < 10; i++) {
        cout << (char) (i + '0');
    }
    cout << endl;
    cout << "uppercase letter:";
    for (int i = 0; i < 26; i++) {
        cout << (char) (i + 'A');
    }
    cout << endl;
    cout << "lowercase letter:";
    for (int i = 0; i < 26; i++) {
        cout << (char) (i + 97);
    }
    cout << endl;
    return 0;
}
